I was heading home from an evening class at Umass-Boston, this was probably about 3 years ago. I was sitting on an end seat near the doors, and a guy wearing jogging attire/loose shorts was sitting directly across from me. It may have been the same guy that has been mentioned here already. His thing was hanging out of the shorts leg, but this time, since a female was sitting across from him (me), he was playing with it. Staring at me with a goofy smile, and jerking off. Needless to say, even though it wasn't my stop, I was off the train by Broadway.